Guess what ! The relay that came with my 1205 set (2504) is indeed a 5V relay but there’s no diode mounted on the pcb inside the transparent cube
So I thought, maybe the diode is inside the relay. The relay manufacturer states that there’s no diode mounted inside the relay.
The idea using a 5V relay has its advantages. It’s more sensitive and you can build your circuits using resistors or other components in series with it.
I still believe that our battery voltage (and certainly with the power adapter) is way too high.
When using a resistor of 120 Ohm in series with it keeps the voltage at 5V across the relay and will save our battery life !
It is probably the best to adapt the experiments in the manuals. Since the white cover has rather fragile tabs, I don’t like the idea to change the relay when broken.
Time to do some tests about the diode. Is it there or is it not ?
I keep you guys informed.